Effect of lung resection on regional lung function assessed by133Xe radiospirometry

Abstract

The regional lung function of 39 patients, 19 with lung cancer and 20 with a non-malignant condition, was studied radiospirometrically before partial lung resection and 2, 6, and 12 months postoperatively. Dynamic spirometry was also performed at each stage. Initially, the postoperative reduction of total FEV1 was 19% and of VC 18%. There was 26% reduction of unilateral ventilation, 34% of perfusion and 30% of VC at two months post-operatively. At six months there was significant improvement in all parameters, whereas at twelve months there was no further notable change with the exception of total VC. At twelve months the reduction of FEV1 was 14% and of VC 8%. The unilateral perfusion was reduced 30%, ventilation 19%, and VC 17%. The .V/.Q ratio was 1.00 preoperatively and 1.11 12 months post-operatively. The results show that the final reduction of both unilateral and total function caused by partial lung resection is smaller than would be expected considering the anatomical extent of the operation. However, the .V/.Q mismatch ensuing from the operation may increase the functional impairment. Lung function appears to become stabilized at its permanent postoperative level during the first six months after operation.